Early isolation=dull chameleons????

[kinyonga]

http://www.abc.net.au/science/articles/2014/01/22/3928600.htm

 

[DeremensisBlue]

This study showed that chameleons are living organisms that adjust to competition. It showed that a chameleon not exposed to others that will take its food away does not show the same urgency as one who is in danger of going hungry.

The responses they developed in the group babies were stress responses in answer to the bullying and competitive dynamic we see when chameleons are together. You can see the eating response in humans too. Take a look at how quickly kids from a large family grab food at dinner versus an only child. The researchers from this study would conclude that the single child has less of a feeding response. While this could be argued, the question we have to ask as keepers is what is healthier. We sure like it when chameleons eat and we want it to happen on our time scale. But do we want to raise our chameleons worried about losing their days meal just so we get the immediate feeding response we desire?

Color: I'd like to see a study on these babies as adults. Have they truly lost their color pallet? Or is it just that the need to give a bright warning display from the stress of bullying is not there? Once again, just because we like bright colors doesn't mean that showing them is a good thing. If the conclusion of this study is to be played out then we would have very dull veiled chameleons in the many homes that have a single animal.


Bill

 

[mmminyard]

Love the comparison to a single child having less of a feeding response than a child that has to compete with siblings!

 

[Mike Fisher]

Goes to show that the old school method of group raising then sorting by size into smaller groups until a certain age/size where they go into individual enclosures has some merit. I've always contended that raising them individually from hatch might give problems socially especially if you ever intend to breed those individuals.

 

[DeremensisBlue]

Goes to show that the old school method of group raising then sorting by size into smaller groups until a certain age/size where they go into individual enclosures has some merit. I've always contended that raising them individually from hatch might give problems socially especially if you ever intend to breed those individuals.

The babies I have raised individually have had no problem mating. What experience did you have where raising them individually created problems down the line?

For them to require social interaction to successfully reproduce it would necessitate that they interact on some level in the wild or else they would not be able to reproduce. Usually species that require learning as babies are pack animals or at least have a mothering instinct. As chameleons disperse once they hatch (and mom is long gone) a learning requirement would be burdensome.

I have had captive generations have less desire to breed (raised as individuals and others in groups). I am more likely to finger a dietary component in that. Much like we sometimes see less warty appearances in captive generations. I have little doubt that is dietary related even though I have not isolated which part it is.

I am not discounting that there could be an important place for competition. Perhaps chance interactions in the wild get the testosterone flowing and build up a male into the strongest he can be. But if this is the case (and I just whipped up this scenario without evidence), then we should find a better way of replicating it using weekly sessions with a mirror instead of subjecting them to daily stress from competition and physical damage that we often see. Nipped tails and scars from biting and clawing are not uncommon in co-habitating babies. Raising babies as a group is unnatural and a product of our convenience with limited time, space, and resources. If they need a component of social interaction I think we should find a better way to provide it.

 

[Mike Fisher]

The babies I have raised individually have had no problem mating. What experience did you have where raising them individually created problems down the line?

None. I've never raised them individually from hatch. Always in small groups for a few weeks.

I did say "might", as in conjecture. Not criticizing anyone's husbandry. The study speaks for itself.

 

[laurie]

I have a small "mini study". I raised my last clutch in individual baby cages. They grew faster, ate better, and were much more active. One clutch is not a big deal, but I could tell the difference, and I plan to raise all my clutches in individual cages. I love not having to worry if a cham is eating, or getting bullied. You can take a quick look at the bottom of the cage and know if each one is eating, and how much. I have raised babies together and single. Mine will be raised alone in the future. JMO

 

[Dooley1]

Thanks for the post Lynda!

It was very interesting and also nice to see a study focused on chameleons.

It was a very small control group-VERY small. All I took from that was some very weak speculation based off of a couple individuals. But hey, maybe future studies will add more insight if done with larger populations or in the field, as the author said.

The amount of variables involved makes me wonder if this study was even worth publishing.

***A small group of ONE species (every species is different)-that makes the title subject "chameleons" kind of a sweeping statement

According to the article, "Chameleons are known to hatch together and disperse slowly so they may well spend time with their siblings, says Ballen."-Where are her sources? Chameleons are known to do that? I don't know if that is common knowledge.

***Did they only test reactions of juveniles or waited until they were all fully-grown? I think this answers it.

"To investigate the impact such interactions would have on later life, she and colleagues studied the behaviour of about 40 veiled chameleon (Chamaeleo calyptratus) hatchlings in the laboratory.-Apparently 2 month old chameleons are a good gauge "on later life". I suppose technically it is later-ha.

As I see from the media, there's a new study every day to contradict the old one. Let's wait for the next study to show how veiled chameleons raised in groups are duller and shyer...

Again Lynda-thanks! You always find great articles to share with the forum!

Chris Anderson-am I being too harsh? You have conducted controlled studies with Bradypodion. Maybe I'm more cynical than I should be.

 

[waynek]

there is a chance that this is not the same for all species of chameleon . maybe hatchling veileds occur in such large densities (30 plus eggs sometimes ) that this behavior is beneficial . whereas some other species (quads , montium ) have much smaller clutches , so the babies never congregate in such densities . also the vegetation where veileds come from (arabian peninsula ) is not nearly as dense as the vegetation in the mountainous jungles of west Africa thus the young quadricornis would be much less likely to have heavy competition for food than their Arabian counterparts . any study based on 1 species and then applied to all similar species makes such an application obviously flawed . also how would this study apply to chamaeleo namaquensis ?

 

[Chris Anderson]

Chris Anderson-am I being too harsh? You have conducted controlled studies with Bradypodion. Maybe I'm more cynical than I should be.

Yeah, you're being too harsh in this case I think. This is an excellent example where interpretation of the findings of a study based on the media coverage of that article is misleading. I highly recommend anyone interested get a copy of the actual publication (http://www.sciencedirect.com/science/article/pii/S0003347213005186) and read it rather than judge it on the media coverage, which is always sensationalized and distilled to what they think is catchy and will grab headlines. I suspect anyone without institutional access will not be able to download the full publication, but typically if you contact the corresponding author (they are denoted by a symbol of some type after their name in the author list and their contact information is almost always listed), they are happy to send you a PDF.

Just to dispel a few misconceptions, however, here are a few comments:

First, while the media release is focused on color change in general as the result of the group vs individual rearing, the article itself is more concerned with the outcome (i.e., dominant vs submissive behavior) of social interactions between individuals from different rearing groups. They use color as one measure to quantify the responses of each individual during interactions. They found (among other things) that while aggression level (specific behaviors are outlined in the paper) was not effected by rearing group, that individually reared animals exhibited more submissive behaviors than those raised in groups and that they adopted darker colors as well. We all are fairly familiar with how color relates to dominance and submissive behavior in chameleons, so this should not be particularly surprising given the findings related to submissive behaviors.

Next, despite the generality of the media article attributing the findings to chameleons in general, the title of the paper itself is quite specific emphasizing the particular species and age group: "Effects of early social isolation on the behaviour and performance of juvenile lizards, Chamaeleo calyptratus". The authors do specify that "sensitivity to early social environment may differ between species within lineages, rather than be present versus absent in entire groups" and go on to state that "The potential influence of an individual’s social environment during juvenile life on its success in contests during adult life has yet to be experimentally evaluated."

Additionally, while statements in the media release are provided without citations, such comments include supporting references in the article itself (including those regarding mass hatching, low dispersal ability, and hatchling aggregation).

I think in general Bill's summary of social history effecting future behavior is particularly relevant to this paper, with one of their main conclusions being that "encounters with conspecifics early in life may shape a chameleon’s subsequent behaviour, as it does in many species of endothermic vertebrates." The authors go on to suggest that "The neonates that were reared in social groups (rather than isolation) may have benefited from early exposure to competition from conspecifics, favouring behaviours that enable a lizard to seize a prey item before it is taken by a conspecific; and familiarity with intraspecific agonistic encounters may also have facilitated an individual’s performance in social tasks." One of the most important points of this study, however, is that early social experience does not only effect behavior in "higher" vertebrates like birds and mammals, but that reptiles too experience social learning/conditioning.

Chris

 

[JacobH]

One of the most important points of this study, however, is that early social experience does not only effect behavior in "higher" vertebrates like birds and mammals, but that reptiles too experience social learning/conditioning.

I'd agree with this statement, though I'd never have thought that was one of the main points when just reading the ABC article.

I didn't have to log in with any password or user name, it only had me find and select the name of my university.

 

[waynek]

shows how the mainstream media takes things out of context so often .

 

[Dooley1]

Yeah, you're being too harsh in this case I think. This is an excellent example where interpretation of the findings of a study based on the media coverage of that article is misleading. I highly recommend anyone interested get a copy of the actual publication (http://www.sciencedirect.com/science/article/pii/S0003347213005186) and read it rather than judge it on the media coverage...

Chris

Chris,

Thank you for elaborating. Looks like I judged without the facts. Thank you for posting the link. I downloaded the PDF so I'll read it over.

 

[kinyonga]

Just so everyone knows...When I post articles like this (under a single topic and not in reply to someone's post) its done for interest and not because I agree or disagree with it (unless I make a comment in the post to say differently).